This document discusses various types of bioenergy including biomass, biogas, and biofuels. It defines biomass as a renewable energy source derived from living or recently living organisms. Key types of biomass discussed include wood, agricultural waste, solid waste, and landfill gas. Methods of converting biomass to energy include burning, bacterial decay, fermentation, and thermal or chemical conversion. Biogas is produced via the bacterial breakdown of organic waste. Algae and crops can be converted to liquid biofuels like ethanol or biodiesel. While bioenergy has benefits like being renewable and reducing emissions, it also has disadvantages like being expensive to produce and store and requiring significant space.

1. Bio-Energy
Dr Fayaz A. Malla
Assistant Professor, Environmental
Sciences, GDC Tral
Higher Education Department, Govt.
of J&K

2. What is biomass?
• Biomass is a renewable energy source that is
derived from living or recently living organisms.
• Biomass includes biological material, not
organic material like coal.
• Energy derived from biomass is mostly used to
generate electricity or to produce heat.
• Thermal energy is extracted by means of
combustion.
• Biomass can be chemically and biochemically
treated to convert it to a energy-rich fuel.

3. Types of Biomass
Wood and Agricultural Biomass
Wood-logs, chips, bark, and sawdust-accounts for about 79
percent of biomass energy.
Solid Waste
A ton (2,000 pounds) of garbage contains about as much
heat energy, as pounds of coal. The main advantage of
burning solid waste is it reduces the amount of garbage
dumped in landfills by 60 to 90 percent and reduces the
cost of landfill disposal.
Landfill Gas
Decomposition process is slowed in the artificial
environment of a landfill, a substance called methane gas
is still produced as the waste decays.
Alcohol Fuels
Wheat, corn, and other crops can be converted into a
variety of liquid fuels including ethanol and methanol.

4. Usually, we burn wood and use its energy for
heating. Burning, though, is not the only way to
convert biomass energy into a usable energy source.
There are four ways:
Burning
We can bum biomass in special plants to produce
steam for making electricity, or we can burn it to
provide heat for industries and homes.
Bacterial Decay
Bacteria feed on dead plants and animals, producing
a gas called methane. This is a natural process that
happens whenever waste decays. Methane is the
same thing as natural gas, the gas sold by natural
gas utilities.
Fermentation
Adding a yeast to biomass produces an alcohol
called ethanol. This is how wine, beer, and liquor are
made. Wine is just fermented grape juice.
Conversion
Biomass can be converted into gas or liquid fuels by
using chemicals or heat. In India, cow manure is
converted to methane gas to produce electricity.
Methane gas can also be converted to methanol, a
liquid form of methane
Using Biomass Energy

5. Something to
know…
• Biomass has a smaller
energy content for its bulk
than fossil fuels
• Costs of labor,
transportation, and storage
would then be higher

6. Biofuels and Biodiesels
Biofuels are created from vegetable or
animal-based oils (Ex: canola or soybean oil,
palm oil, grease, sewage or leftover trash) It
is used and fuels for vehicles.
Biodiesel is also a type of fuel created by
vegetable or animal oils, but it is often
blended with regular diesel. Biodiesel is a
cleaner alternative to diesel. But not all
vehicles can use diesel. The calorific value of
biodiesel is about 37.27 MJ/kg

7. Advantages for
Biomass, Biogas,
and Biofuel
1. It’s renewable - You will always have a source for
biomass (Crops and garbage)
2. Abundant - Biomass is available all over the world
3. Cheaper than other fuels - It cost ⅓ less than fossil
fuel which can save you a lot of money
4. Carbon neutral - Biomass is a part of the carbon
cycle. It is a clean source and do not contribute to
global warming

8. ENVIRONMENTAL ADVANTAGES
• Renewable resource
• Reduces landfills
• Protects clean water supplies
• Reduces acid rain and smog
• Reduces greenhouse gases
• Carbon dioxide
• Methane

9. Sources of Biofuels
Algae
Ethanol
Vegetable oil
Biogas
Syngas
Blended Biodiesel

11. Ethanol-how is it currently
used and made?
• Ethanol: alcohol by fermenting the
sugars found in plants, it is often
blended with gasoline.
• The way ethanol is produced in the
U.S. by using corn to be produced into
ethanol.

13. Biodiesel
Biodiesel is a fuel made from vegetable or animal oils that is often blended with regular diesel fuel.
Pros
• Uses waste for fuel
• Resources are cheaper
• Reduced Methane
(greenhouse gas)
Cons
• Needs lots of maintenance
• Less potential energy
• Thought to lead to higher
pollution and more health
problems.

14. Algae as a Biofuel
 Algae grows 30 times as fast as plants
and it stores up to half of its total
body mass as oil; meaning that it has
a greater oil supply to use as fuel.
 It is very expensive to run plants to
properly culture algae, making it a
less likely source for commercial use.

15. Algae as a Biofuel
Pros:
● It grows a lot faster.
● Can be grown in a controlled
area and at a controlled amount.
● Holds more oil than typical plants
(that are used for biofuel)
Cons:
● More expensive.
● Grows rapidly.
● Harder to get oils out.

16. Biogas
 Biogas is defined as a mixture of different gases produced by the breakdown of once living organisms in the absence of
oxygen. Biogas can be produced from raw materials such as agricultural waste, manure, municipal waste, plant material,
sewage, green waste, or food waste.
 Biogas contains roughly 50-70 percent methane, 30-40 percent carbon dioxide, and trace amounts of other gases. The liquid
and solid digested material, called digestate, is frequently used as a soil amendment.
 The calorific value of biogas is about 6 kWh/m3 - this corresponds to about half a litre of diesel oil. The net calorific value
depends on the efficiency of the burners or appliances.

17. Pros of Biogas
• Provides non-polluting and renewable source
• efficient way of energy conversion( saves
fuelwood)
• saves women and children from carrying firewood
and exposure to kitchen smoke
Cons of Biogas
• Difficult to enhance efficiency of biogas systems
• contains some impurities and gas that are harmful
• it is somewhat unstable make it prone to
combustion if methane comes in contact with
oxygen
Biogas

18. Biogas Digester

19. Types of Biogas Plants

20. • Biomass gasification is a mature technology pathway
that uses a controlled process involving heat, steam,
and oxygen to convert biomass to hydrogen and other
products, without combustion.
• Gasification is the process of converting biomass into a
mixture of combustible gases (Syngas or producer gas)
and is performed at a high temperature range of 800–
1000°C. The composition of Syngas depends on the
feedstock used for gasification and typically composed
of 30-60% of CO, 25-30% of H2, 0-5% of CH4, 5-15%
of CO2 and water vapour and sulphur compound to
some extent with low caloric value (2-15 MJ/Nm3)
Biomass Gasification

21. BIOMASS AND CARBON EMMISIONS
• Biomass emits carbon dioxide
when it naturally decays and
when it is used as an energy
source
• Living biomass in plants and
trees absorbs carbon dioxide
from the atmosphere through
photosynthesis
• Biomass causes a closed cycle
with no net emissions of
greenhouse gases

22. Disadvantages for Biomass, Biogas, and Biofuel
1. Expensive - Biomass is expensive to set up and store
2. Requires a lot of space - We need a lot of space to store all the
energy
3. Crop and forest residues often contain high concentrations of
important nutrients
4. If the residue is harvested as energy, the nutrients can be lost to
the surrounding environment.
5. Other synthetic chemical nutrients or fertilizers can later be added
6. More plants and trees must be planted, because they will be used
in a higher quantity

23. Energy Efficiency
Biomass is 52% efficient, so using it is less efficient because it only gives off half of its energy.